Ovarian cancer is a significant disease in women; 1 out of 72 women in the U.S. is diagnosed with ovarian cancer sometime during her lifetime. In 2012, 22,280 women in the U.S. were diagnosed with this illness, and 15,500 women died of this malignancy. Ovarian cancer is disproportionately deadly because this type of cancer lacks any clear early detection or screening test, meaning that most cases of ovarian cancer are not diagnosed until they have reached advanced stages. Thus, ovarian cancer screening is of high clinical interest because the disease is not typically detectable at its early stages, when it is the most curable.
Definitive detection of ovarian cancer presently requires a surgical procedure to obtain cell samples for diagnosis. Since the ovaries are intra-abdominal, laparoscopic or open surgery (laparotomy) must be performed to access the ovaries for evaluation. Furthermore, biopsy of the ovary is not generally recommended by medical guidelines as there exists a risk of spreading the cancer further.
Anatomically, the ovaries are in close proximity of the fimbria at the region of the distal opening or os of the Fallopian tube. Eggs released by the ovary are gathered by the fimbria and transported through the Fallopian tube to the uterus. In ovarian cancer, cells may be deposited in the Fallopian tube; a few of these cells may find their way into the uterus. Cell samples obtained from the uterus may detect ovarian malignancy; however, the incidence of migration of ovarian cancer cells into the uterus is too low to render uterine sampling a reliable diagnostic test for ovarian malignancy. A higher number of ovarian cancer cells migrate to the Fallopian tube; this number increases in the distal portion of the tube, near the distal os. The ability to test cells in the Fallopian tube for malignancy would be of considerable clinical value for the early detection and treatment of such cancers, if such could be performed without concern about spreading cancerous cells. Additionally, a need exists to distinguish ovarian cancers from Fallopian tube cancers based on the finding of abnormal cells in the Fallopian tubes for several reasons including the varying treatment regimens therebetween.
However, the introduction of a diagnostic device into the Fallopian tube is problematic since the Fallopian tube is extremely fragile and prone to perforation during passage of most devices. Perforation generally occurs at the uterotubal junction (UTJ), a constriction that occurs approximately 1 cm distal to the proximal os (opening) of the Fallopian tube in the uterus. The lumen size at this constriction may be as small as 0.3 mm or 0.5 mm, while the lumen size of the Fallopian tube adjacent to the uterotubal junction is approximately 1 mm. FIG. 1 depicts a cross-sectioned view of the Fallopian tube 1 with the uterotubal junction (UTJ) 2 that connects the uterus 4 to the ovaries 6.
Thus, there exists a need for a device and process to allow cell samples to be obtained from Fallopian tube for evaluation of ovarian cancer in a minimally invasively fashion and, particularly without the need for a skin incision. There further exists a need for securing a sample of representative cells from the Fallopian tube with a catheter to screen for early stage cancers